A few weeks ago i overheated my 2006 yz450 because while i was riding, the o-ring that seals between the coolant pipe and the cylinder head failed and i unknowingly was losing coolant as i was riding. i was going into a turn and it bogged and stalled and steam or smoke started coming out from under the seat. anyways, i called it a day and packed up and headed home. i was able to get a new o-ring to fix the leak but i soon noticed that the rubber boot thing that covers the spark plug was melted/cracked, so i got a new one and figured that everything would be okay. last week i rode and when i got home i noticed slight oil leak around the base of the cylinder, and my coolant level dropped sufficiently, and it seems that coolant is now getting into my oil. how much damage do you think i may have caused by overheating my bike to the point that it stalled and smoked from under the seat? what steps should i take next? if i need to replace the base gasket should i just install a new top end while its apart? sorry for the long post, i have just been losing sleep over the damage i may have caused.